Aerial for wireless reception



6 1924 2 Shams-52m; 1

Inventor. Paul 6? Kiwi- 9 P. E. KLOPSTEG AERIAL FOR WIRELESS RECEPTION Filed Dec.

Sept. 1,1926.

P. E; KLOPSTEG. AERIAL FOR WIRELESS RECEPTION Filed $6- 6. 1924 2 Sheets-Sheet 2 Patented Sept. 7,1926.

UNITED STATES PATENT OFFICE.

PAUL E. KLOPSTEG, OF CHICAGO, ILLINOIS, ASSIGNOB T0 CENTRAL SCIENTIFIC COM- PANY, or CHICAGO, ILLINOIS,

A CORPORATION OF ILLINOIS.

AERIAL FOR WIRELESS RECEPTION.

Application. filed December 6,1924. Serial No. 754,300.

This invention relates to apparatus for and secured in place by the bolt, after which receiving wireless signals and has for its principal object to increase the inductance for a given amount of wire, to reduce the distributed capacitance (corresponding to the inductance), and to reduce the energy losses at high frequency. A subordinate object is to provide a loop aerial that can be readily f0 ded into a compact bundle when not in use, and readily extended for use.

Further ob'ects and advantages of the invention' will hecome apparent as the disclosure proceeds and the description is read in connection with the accompanying drawings, in which- Fig. 1 is a side elevation of aloop aerial embodying this invention;

Fig. 2 is an edge elevation of the construction shown in Fig. 1;

Fig. 3 is a plan view of the construction shown in Fig. 1;

Fig. 4 is a perspective of a fragment of the support for the conductor;

Fig. 5 is an elevation of a fragment corresponding to that shown in Fig. 4;

'Fig. 6 is a section of a fragment of the support taken on' the line 6-6 of Fig. 1;

7- is a side elevation partly in section of the base for the aerial support;

Fig. 8 is an exploded view of the base;

Fig. 9 is a perspective view of the package formed by folding the aerial and inserting it in a tube;

Fig. 10 is an edge view of. a modified winding of the conductor, and

Fig. 11 is a fragmentary view illustrat ng a further modification.

Referring to Figs. 1 and 6, the trameof the aerial includes a plurality of arms 10 having their inner ends clamped in sockets ill in a hub 12,,which latter is composed of mating halves 13 and 14, having corresponding pockets 15, which together maltethe arm receiving sockets. The halves ot the hub are secured together by a: bolt 16 threaded into one half at 17 and having a shoulder 18 for engagement with the other half. The belt is equipped with a suitable knob 19 to facilitateits rotation.

By removing the bolt the one half of the hub may be displaced and the arms folded, umbrella fashion, without removing their inner ends from the pockets in the remaining hub half. The displaced half may thenbe placed against its. mate on the opposite side the frame with the conductor may be inserted in tube 20, as illustrated in Fig. 9.

The hub and bolt are made of non conducting material such as bakelite, hard rubber and the like, and. the arms are preferably made of wood or bakelite.

The outer end of each arm carries a strip of insulating material 21 (Figs. 4 and 5) equipped with two series of seats 22 in staggered relation, and preferably at the angles of equilateral triangles, as shown in Fig. 5. As shown, these seats take the form of notches in the insulating strips which are closed by binding strips 23, secured in place by cement and reenforced with dowels 24 of insulating material. The arms are split for suitable depth to receive the strips 21 which are secured in place by cement and by dowels 25.

One arm is provided with an extension 26 having a pintle 27 at its lower end received in a socket 28 whereby the frame with the conductor is permitted free rotary movement relative to the base. This latter is composed of two sleepers 29 provided with half-lap mortises and clamped by a bolt 30'Which contains the socket 28. The end portions of the sleepers are fitted with felt, or other soft feet 31.

The extension 26 is equipped with a terminal block 32 made of insulating material and carrying binding posts 33 and 34. A conductor 35 connected to the binding post 33 is led upwardly, as indicated at 36, and rested on the inner seat of the bottom strip 21 at the opposite side of Fig. 1. From this seat it is wound to the left, as indicated at 37,. and rested upon the seats on the back side of the next two arms. Then it is brought across to the front side of Fig. 1, as indicated at 38, and rested upon the inner seats at the front side of the next five arms, which brings it to the point 39 when it is taken back to the opposite side of the frame and laid on the seats on that side of the next five arms, and so on, until the opposite end 40 of the conductor is attached to the binding post 34;.

' By staggering the seats on the supports adjacent loops of the conductor are spaced at a maximum distance and by laying alternate loops on alternate sets of seats the aerial to the other between each two acent arms throughout each loop so that 'on ziazag sacross the frame. Corsides of al ernate polygons are parallel throughout and correspoiuling sides of ad acent polygons cross throughout. This construction *an only be had with an odd number of arms whereas the. wi' shown in Fig. 1 may be used either with an odd or an even number ot arms.

The maximum amount conductor in ea oh loop is approached as that loop approaches a true circle. The greater the ninnher oi arms in the support the greater the munber of sides in the polygons, and the closer the approach the circle. J. trams having live arins can be very economically produced and a polygon having five sides approaches a circle suiliciently close to give good practical results.

I In the modified construction shown in Pie: 11. the strips 21 are rep aced by strips A to the arms 10, and the ll lvine" crosswise seats are arranged in inner and outer series and staggered: as in the strips 21. For convenience in winch the strips may be no'ched. as indicated at 2, to provide alternate seats and i"- necegsar; reentorcing strip may be sec red LO the upper portion each strip ll, a'ter the winding is done.

This construction has the anvantagife that the average size of the polygons is increased, which permits the same amount of conduct r to be contained in a smaller number of loops, and increases the inductance for the same amount of conductor. However, such a construction does not told compactly as the term shown in Fig. 1.

it difference of potential between any two portions of the conductor in a loop aerial s up electric lines of force between them which changes direction at twice the freqnency ot the incoming signal and if the lines of force pass through a solid dielectric there is a loss due to the changes of direction which are thought to cause a chance of polarization in the molecules in the dielectric. In short, the changes of direction produce a loss through dielectric hysteresis. These lines of electric force are more numerous if the two portions of the conductor under consideration are close together. Hence it follows that; the separation of any functional portion of the conductor in an aerial from all other tunctional portions should he as great as possible; the distance should be great; especially between those portions between which the potential difference at an instant is large; and solid dielectrics should be kept out of such regions as completely as possible. An cxan'iination oi the constructions above described will show that they meet these requirements.

Any conductor carrying an electric current has associated with it lines oi. magnetic force, and any metallic object near the conductor will be penetrated by these lines of magnetic force. It the current alternates at high t'recnienc). the lines oi magnetic force change direction at twice this treqncncv, n l the lines which pa s through the metallic object will set up in that object electric eddy currents which absorb energy from the inciting cause and thus, as in the case of 'adio wireless signals, reduce the already feeble energy available for reproduction. Accoroing to this invention all metal is eliminated from the magnetic lield and losses through eddy currents are avoided. By saving: the energy usuallv wasted in dielectric and eddy current losses, the invention permits sharper tuning, and b v re.

ducing distributed capacitance to a very lo value it permits timing to a higher treouency with a given tuning condenser.

i Since the energy of wireless signals is and sharp tuning requires a in inr of energy hv resis"auce in the ondu preferable to use separately in ula ed stranded wire. known to the tra e as Litzendraht, or high frequency cable. The arrangement of the loops according to this invention permits the necessary amount. ot inductance to be .htained with a minimum length of conductor, and this reduces the cost of using the most ctiicient. materials.

I claim as my invention 1. In an aerial, a support and a condu tor carried thereby arranged in a plurality of loops in staggered relation at each side ol the support.

2. In an aerial, a support having a plural it; of sets of seats, the seats o l each set lying in substantially the same plane and situated in the relation of angles in a polygon, the seats of one set in each three adjacent sets being opposite to the spaces between the corresponding seats of the other two sets, and a conductor wound on said seats in loops.

3. In an aerial, a support including a plurality of arms in angular relation, opposed series of seats in staggered relation on each arm, corresponding series on the several arms forming sets of seats defining substantially concentric polygons, and a conductor wound upon said seats.

4. In an aerial, a support including, a plurality of arms in angular relation, opposed series of seats in staggered relation on each arm, corresponding series on the several arms forming sets of seats defining substantially concentric polygons, a conductor wound upon said seats, and forming alternate polygons in alternate sets.

5. In an aerial, a support including an odd number of arms in angular relation, opposed series of seats in staggered relation on each arm, corresponding series on the several arms forming sets of seats defining substantially concentric polygons and a conductor wound upon said seats.

6. In an aerial, two opposed sets of loops spaced apart with the loops of each set opposite to the spaces between loops of the opposed sets, and adjacent loops of each set connected bythe intermediate loop of the opposite set.

7. A foldable element comprising a plurality of loops of a conductor and a support therefor including arms in angular relation, and means for making the loops fast to the arms, a hub made of sections having sockets to receive adjacent ends of the arms, and means for clamping the sections together and to the arms whereby the arms may be released from the hub and folded together.

8. A foldable element comprising a plurality of loops of a conductor and a support therefor including arms in angular relation and means for making the loops fast to the arms, a hub composed of mating halves provided with sockets receiving the adjacent ends of the arms and a bolt for clamping the halves together and to the arms, whereby the arms ma be released from the hub and folded toget er.

9. In an aerial, a plurality of loops of a conductor, a frame for said loops including an arm having a pintle projecting beyond the loopsand a base including a plurality of sleepers and a bolt securing the sleepers together and having a socket to receive the pintle.

10.. In an aerial, a support including a I plurality of arms in angular relation, opposed series of seats on each arm in corresponding position on the several arms, the

seats in one series being opposite to the spaces between the adjacent seats in the opposed series, corresponding seats on the several arms forming sets of seats lying in substantially the same plane and at the angles of substantially concentric polygons, and a conductor wound upon said seats in loops forming polygons.

11. In an aerial, a support having a plu rality of sets of seats, the seats of each set lying in substantially the same plane and situated in the relation of angles in a polygon, the seats of one set in each three adjacent sets being opposite to the spaces between the corresponding seats of the other two sets, a conductor wound upon said seats in loops, with the remote loops lengthwise with respect to the conductor at a maximum distance on said support.

12. An aerial corresponding to that defined by claim 11, in which successive polygons rest upon alternate sets of seats.

13. An aerial corresponding to that defined by claim 11, in which the arms are of an odd number.

1 1. In an aerial, a support including a plurality of arms in angular relation, a series of seats on opposite sides of each arm with the seats of one series opposite to the spaces between the seats of the opposed series, all those seats on the corresponding sides of the several arms lying in substantially the same plane and at the angles of substantially concentric polygons, and a conductor laid on said seats in polygonal loops with successive loops resting on seats on opposite sides of the support.

15. In an aerial, a support, a set of loops on opposite sides of the support with the loops of each set opposite to the space be tween the loops of the other set, and adjacent loops of each set connected by the intermediate loop of the opposite set.

In testimony whereof I aflix my signature.

PAUL E. KLOPSTEG. 

